Laboratory device



' March 29, 1949. w. DRUGE LABORATORY DEVICE Filed May 20, 1947 IN V ENTOR.

Lucien W .Druge Alforney Patented Mar. 29, 1949 LABORATORY DEVICE LucienW. Druge, Riverside, 111., assignor to Universal Oil Products Company,Chicago, 111., a

corporation of Delaware Application May 20, 1947, Serial No. 749,227

1 Claim.

This invention relates to an improved laboratory device for convertingan ordinary funnel into a vacuum funnel for rapid filtering. Morespecifically the novel device provides a conical insert member suitablefor holding a filter paper within a funnel in a manner which permitsvacuum filtering, and in addition thereto, the device provides for theeasy removal of the filter paper and its retained material from thefunnel.

The usual type of vacuum funnel, such as the Buchner funnel, has anon-removable perforated bottom and the filter paper, which is placedwithin the funnel, must ordinarily be dug out of the funnel after use,rather than easily lifted out. The vacuum funnel also has a relativelyflat perforated bottom section such that the filter paper, cloth, orother filtering membrane, must 7 rest in a substantially fiat mannerwithin the funnel and a certain amount of the filter-cake, or retainedparticles, are deposited on the walls of the funnel and therefore arenot entirely recovered within the limits of the paper.

The principal object of this invention is to provide a device which maybe inserted in an ordinary sloping wall type of funnel and provide meansfor converting the latter into a vacuum funnel.

It is also an object of the invention to provide a removable insert fora funnel which is adapted to hold a filter paper in a well supportedmanner and which will permit easy removal of the paper with its retainedfiltered particles.

Briefly, the device of my invention comprises, a perforated cone-shapedmember which is adapted to be inserted within an ordinary sloping wallfunnel, a gasket member attached to and encircling the outer peripheryof the insert member at the enlarged end thereof, with the gasket memberbeing arranged to project slightly from the outer surface of thecone-shaped insert and providing thereby a sealing and supporting ringfor the device when it is placed within a funnel. The perforatedcone-shaped member thus provides means for holding a filter paper in awell supported manner at a spaced distance from the inner sloping wallof the funnel, and such that there is the necessary space for applyingvacuum to the entire insert to efiect rapid filtering. The upper andouter surface of the perforated member is preferably provided with agroove or recess such that the gasket may be maintained in a relativelyfixed position and be tightly sealed to the insert member. Also, theasket member is preferably of a soft rubber-like or resilient materialsuch that a good air seal may be obtained at the upper end of the spaceprovided between the perforated insert member and the funnel wall.

The design and construction of this novel insert is such that it notonly provides a vacuum type of funnel, but simultaneously gives the usermany desirable advantages. A filter paper may be easily placed withinthe insert, and when it is being used there is no danger of the lowertip end of the filter paper being ruptured and the contents spilled.Also, there is no difiiculty in removing the paper and the retainedmaterial from the funnel as the entire insert and paper may be removedtogether. In many laboratories, it is a practice to place a backingstrip of gauze around the lower end of a filter paper in order toprevent rupturing of the tip end, however, use of the insert member willobviate the necessity of taking this prevention and will make allfiltering operations in general much easier to perform. The cone-shapedinsert may be constructed of many types of materials such as glass, aceramic material, metal or metal alloy, while the gasket member may bemade of rubber or other soft rubber-like material.

Another advantageous feature of the novel device, is that it may be madein a very inexpensive manner to fit most standard sized funnels and maybe used therein to carry out ordinary filtering operations, in additionto vacuum filtering. Since the device may be used to carry out vacuumfiltering, one or more of them may be maintained in the laboratory tosupplant the more expensive type of vacuum funnels.

The accompanying drawing will serve to illustrate the construction ofone embodiment of the device, as well as to indicate how it may beinserted in an ordinary type of funnel.

Referring now to the drawing, there is shown a perforated cone shapedmember 1, which is adapted to be placed within any ordinary type ofsloping wall funnel 2, the latter being indicated by the dotted lines. Agasket member 8 is placed around the upper and exterior side wall of theinsert member I. This gasket 3 is prefer-' ably placed near the upperend of the device at a point above the multiplicity of perforations 4,which are provided through the wall of the insert member I. The asket isalso attached to the cone shaped member I in a manner to projectslightly from the outer surface thereof and to thereby provide a smallannular space between the surface of the insert member and the innerwall of the funnel when the device is placed and supported within anordinary type of funnel. In a preferable embodiment of the device, aslight groove or recess is provided within the wall of the cone-shapedmember I in order to accommodate the gasket 3 such that it will beretained in a fixed position and will not slip from the outer wall ofthe device.

In operating and using the device to convert an ordinary. type of funnelinto a vacuum funnel,

1e insert is placed within a funnel and the combination is used insubstantially the same manner that a Buchner funnel is employed. Thefunnel 2 may be inserted into a receiving bottle, with a rubber stopperor other sealing means, and,

vacuum applied to the receiving bottle such that filtrate is rapidlydrawn through the device and collected therein while the filteredparticles or filter-cake is retained on the filter paper, or other likememberane, which has been inserted within the perforated cone-shapedinsert, I. The vacuum action from the receiving bottle is exerteduniformly around theinsert I since the gasket 3 serves to support themember in a spaced manner from the wall of the funnel 2. After thefiltrate has been drawn through the device and the filtered material isretained therein, the entire insert with the filter paper and materialmay be removed from the funnel 2, and the recovered material subjectedto further desired treatment or analysis, without there being any lossof the material.

As previously noted hereinabove, the drawing shows one preferableembodiment, however, the invention is not to be limited strictlyto-theconstruction and arrangement which is shown. The and spacing'ofthe perforations within the cone-shaped member may be varied to providevarying percentages of open area to total area, or the perforations maybe of varying shapes, such as slots, squares, or the like. The gasketmember 3 may have other than a rectangular cross-section and may also beattached to the cone 40 member I in a somewhat different manner fromthat illustrated, so long as it is made to project slightly from theouter surface of the perforated insert and provides the necessary airspace around the insert when placed within a funnel.

I claim as my invention:

A device for holding a filter paper and for converting a funnel to oneof the vacuum type, comprising in combination, a perforated coneshapedmember constructed of a single piece of rigid material and adaptable forinsertion within a sloping wall funnel, a gasket retaining recess on theexterior surface of said one-piece member at the upper enlarged portionthereof and a gasket member positioned within said recess, said gasketbeing tightly attached and sealed to said member within said recess andof a size sufllcient to project ashort distance from the outer surfaceof said conical perforated member, said gasket providing thereby meansfor sealing and supporting said insert within said funnel at a spaceddistance from the inner wall of the latter.

LUCIEN W. DRUGE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date Re 6,614 Heermance Aug. 24, 1875155,386 Richardson et a1. Sept. 29, 1874 1,081,574 Boeck Dec. 16, 19131,501,073 Stead July 15, 1924 2,331,234 Rush Oct. 5, 1943 FOREIGNPATENTS Number Country Date 8,375 Great Britain 1886 14,764 GreatBritain. 1912 24,308 Norway Mar. 2, 1914

